🧬 Population Genetics & Mendelian Inheritance
Hardy-Weinberg Equilibrium & Allele Frequency Calculator
Compute dominant allele frequency ($p$), recessive frequency ($q$), homozygous dominant ($p^2$), heterozygous carriers ($2pq$), and homozygous recessive ($q^2$) genotypes ($p^2 + 2pq + q^2 = 1$).
🧬 Cystic Fibrosis ($q^2 = 1/2,500$)
🧪 PKU ($q^2 = 1/10,000$)
👁️ Blue Eyes ($q^2 = 9\%$)
🩸 Rh-Negative ($q^2 = 16\%$)
Population Input Options
Example: 1 in 2500 = 0.0004
Heterozygous Carrier Frequency (2pq)
3.92% (1 in 26 people)
Homozygous ($p^2$)
96.04%
9,604 ind.
Heterozygous ($2pq$)
3.92%
392 carriers
Recessive ($q^2$)
0.04%
4 affected
💡 Hardy-Weinberg Equation:
$$p^2 + 2pq + q^2 = (0.98)^2 + 2(0.98)(0.02) + (0.02)^2 = 0.9604 + 0.0392 + 0.0004 = 1.000$$
The Hardy-Weinberg Principle
Formulated independently by G. H. Hardy and Wilhelm Weinberg in 1908:
- Allele Frequencies: $$p + q = 1 \implies p = 1 - q$$
- Genotype Frequencies: $$p^2 + 2pq + q^2 = 1$$
- Carrier Prevalence: For rare recessive conditions ($q \ll 1$), carrier frequency is approximately $2pq \approx 2q$, far exceeding the frequency of affected individuals ($q^2$).